Sewing-machine



J. KIEW'IGZ.

SEWING MACHINE.

APPLICATION mm DEC. 12. 1918.

4 SHEETSSHEET Fig.1.

lm/enf'or'. John Kiewicg 1. KIEWICZ.

SEWING MACHINE.

APPLICATION FILE!) DEC- lg. 1918.

1,352,280. PatentedSept 7, 1920. 4 SHEETS-SflEET 3- v I Fig. 3.

l. KIEWICZ.

sewme momma.

APPLICATION HLED DEC- 12, I918- 1,352,280, PatntedSept. 7, 1920.

4 SHEETS-SN EET 4.

Fig; 6.

J7 a I a W Im/erlfor.

' HH y's.

- vices JOHN KIEWICZ, OF BOSTON, MASSACHUSETTS, ASSIGNOR TO THE REECE BUTTCiN' HOLE MACHINE COMPANY, 015 BOSTON, MASSACHUSETTS, A CORPORATION OE MAINE.

SEWING-MACHINE.

Specification of Letters Patent.

Patented Sept. 7, 192%.

Application filed December 12, 1918. Serial No. 266,426.

To all whom it may concern:

Be it known that 1, JOHN Krnwroz, a citizen of the United States, residing at Boston, county ofSuifolk, State of Massachusetts, have invented an improvement in Sewing-Machines, of which the following description, in connection with the accompanying drawing, is a specification, like characters on the drawing representing like parts.

This invention relates to sewing machines of that type which are constructed to sew a short seam and then come to rest automatically,

for cutting the under and upper threads at the end of each sewing operation.

The invention -is herein illustrated as it rotatable turret situated beneath the work-. holding means and which is constructed so that at the end of the stitching operation on any buttonhole the stitch-forming mecha nism and work-holding means are moved relatively from stitching position .to buttonhole-cutting position.

Buttonhole sewing machines of this ty e are commonly madeso that when the stitc forming mechanism is brought to rest upon the completion of a buttonhole, the needle is in raised position above the work and a loop of needle thread passes from beneath the work around the looper'of the under-thread mechanism and back through the Work to the needle, While the under thread passes directly from the work to the under-thread handling mechanism.

In order to form properly the first stitch when the sewing machine is set in operation it is desirable that a certain length of the under thread should be drawn out from the source of supply. My invention contemplates novel means for thus drawing out a length of under thread at the end of the stitching operation and thencutting the under thread so as to leave a proper length for the formation of the first stitch when the sewing. machine is started again. In sewing machines of this type there is a relative movement between the stitch-forming mechanism and the work-holding means after the stitch-forming mechanism has been brought to rest whereby the parts are carried relatively from stitching position to buttonholecutting position. When such relative moveand it has particular reference to de ment takes place While the loop of upper thread is held by the looper of the under thread mechanism, the result is that the loop of needle thread will be enlarged by an amount equal to the relative movement, and if both sides of the enlarged loop of needle thread are then cut close to the work a considerable waste of thread will be entailed. My present invention provides means whereby after the stitch-forming mechanism has been brought to rest the side of the loop of needle. thread which leads to the work is severed before the relative movement of the parts from stitching position to buttonhole-cutting position is. completed so that during such movement the loop will not be enlarged and no extra length of upper or needle thread will be drawn from the source of supply. Hence when the needle thread is cut beneath the work there will be a minimum Waste of thread.

'In order to give an understanding of my invention, I have illustrated in the drawings a selected embodiment thereof which Wlll now be described, after which the novel features will be pointed out in the appended claims.

- Figure l .is a side view of a buttonhole se' 'ing machine embodying my invention;

Fig. 2 is a bottom plan view of the base frame showing the actuatingmeans for the thread pull-off and thread cutter but omitting some of the well-known or usual elements found in. sewing machines of this type} Fig. 3 1s a front view of the under thread mechanism;

Figs. 4 and 5 are each sections on the line 4-4, Fig. 3, showing the parts in different positions;

Fig. 6 is a plan view of the work-holding means and the thread-trimming device;

Figs. 7 and 8 are diagrammatic views showing the operation of the pull-off mem-- turret, I have herein illustrated it as applied to a sewing machine of the type shown in the United States Patent No. 862,238, dated August 6, 1907.

In the machine herein illustrated 1 inditends axially through the turret, said sleeve being reciprocated vertically by the lever 93 which is actuated from suitable cam mechanism on the driving shaft, not shown. As-

sociated with each loo'peris a looper spreader 11, said spreaders being actuated by an oscillatory spreader actuator 12 which is connected by the link 13 to a vertically-reciprocating spindle 14 extending axially through the sleeve 92, said spindle 14 beingactuated from the lever 15 which. in turn is actuated from suitable cam mechanism, not shown. The looper 8 is athread-carrying looper, that is, it is provided at its end with an eye 16 through which the under thread 17 is threaded.

These loopers are operated in timed relation with the movements of the needle and each looper is constructed to enter a loop of needle thread and retain said loop until the needle makes its next descent, the Spreaders operating to spread the loops so that upon each descent of the needle it will pass through a spread loop of its own thread.

The work, indicated by dotted lines at 18, is retained in position on a clamp plate 19 by means of the usual worky clamps 20, said clamps being pivoted to the clamp plate at 21. These clamps may be actuated in any usual way. Each clamp is herein shown as having a' lip 22 which engages an upturned portion 23 carried by clamp-actuating member 24 that is pivoted at 25 to the base frame 1. This member 24 has an arm 26 depending therefrom to which is pivoted at 27 one member 28 of a toggle device, the

other member 29 of said toggle device being pivoted to the base frame at 30 and having an upwardly-extending arm or handle 31 by which the toggle may be actuated. The straightening o the toggle operates through the connection above described to depress the work clamps 20 against the work. 32 indicates the cutter for cutting the buttonhole, said cutter being operated in any usual The parts thus far described with the exception of the means for operating the spreader actuator 12 are or may be all as shown in said Patent No. 862,238, and

, hence do not needany further description.

en a sewing machine of this type isstarted in operation, the work clamps are first actuated to clamp thework against the clamp plate, this being done by straightening the toggle device 28, 29. The stitchforming mechanism and the work-holding means then have a relative movement to carry the parts from buttonhole-cutting position to stitching position. In the particular type of sewing machine herein illustrated this is accomplished by a movement ,of the stitch frame carrying the head 2 and depending portion 7 to the left thereby to bring the needle into 'dotted line position Fig. 1. The stitch-forming mechanism is then set in operation and the stitch-frame and Work-holding means are given a relative feeding movement by the usual feed cam 33 thereby to. cause the formation of overseam stitches down one side of the buttonhole and back along the other side of the buttonhole, it being understood that both the needle 4 and the under thread mechanism have a rotative movement as the stitches are formed around the end of the buttonhole.

When'the stitching operation on the buttonhole has been completed, the stitch-forming mechanism is brought to rest with the needle raised and with a loop 44 of the needle thread retained bythe looper 9. When the stitch-forming mechanism has been thusbrought to rest, then the stitchframe carrying the stitch-forming mechanism is moved to the right into buttonhole-' cutting position, thus bringing the needle 'g ack into the full line position shown in 9 y present invention comprises novel means for drawing off a length of under 7 the eye of the looper which is sufficient in extent so that when the stitching operation is started en another buttonhole, the first stitch will be properly formed. 7

The means for cutting the under thread is situated to operate between the work and the clamp plate 19 and is constructed to sever not only the under thread, but also the stay-cord if one is used. When the sewing. machine comes to rest at the complev tion of a buttonhole with the needle 4 raised a loop 44 of needle thread is retained by the looper 9, as stated above. The thread cutter by which the under thread and staycord are cut is constructed so that it w1ll also cut the upper thread beneath the work.

This thread-cutting operation is performed after the work-holding means and stitchforming mechanism have moved relatively thread will be cut. Hence during such rela tive movement from stitching to buttonhole-cutting position, no extra upper thread will be drawn out by enlarging the loop and thus any unnecessary waste is eliminated.

The means for thus pulling off a length of the under thread 17 is in the form of a pivotally-mounted arm 34 which operates directly beneath the throat-plate 35 of the under thread mechanism and between the latter and the looper 9, said arm being constructed to engage the under thread 17 at a point between the throat-plate 35 and looper thereby to draw a len h of thread from the source of supply. his arm may conveniently be mounted upon the turret 6, and it is herein shown as provided with a verti- (rally-extending stem 36 which is journaled in a suitable bearing 37 carried by the turret 6. The stem 36 has an arm 38 fast thereto.

which is acted upon by a spring 39 that tends normally to hold the arm against the portion 40 of the turret, as seen in Figs. 3 and 4, and when the stem is in this position the arm 34 will occupy the position shown in Fig. .7 relative to the throat-plate 35. hen in this position the arm 34 stands at one side of the throat-plate and thus is entirely out of the way of the operations of the under thread mechanism. When the sewing machine has come to rest upon completing a buttonhole, the stem or shaft 36 is turned thereby to swing the arm34 across beneath the throat-plate 35, and during such movement said arm will engage the under thread 17 and draw out the desired length thereof. The arm is provided with a threadreceiving notch 41 situated so that as said arm has its swinging movement the under thread will enter the notch, said notch preventing the thread from slipping ofi from the arm during its further swinging movement. Any suitable means may be employed for giving the stem 36 its turning movement at the proper time in the cycle of operations. I have herein provided a construction wherein such movement is derived by or through the relative movement between the stitch-forming mechanism and work-holding means as the parts are moving relatively from stitching position to buttonhole-cutting position. When the stitch-forming mechanism comes to rest, the turret is in the position shown in Figs. 3 and 4. As the stltchforming mechanism and work-holding means begin their relative movement from stitching position to buttonhole-cutting position-the turret is rotated through ap roximately 180 into the position shown in ig. 5, and it re-- mains in such position during such further relative movement.

Secured to the base frame 1 of the machine isa finger or stop arm 42 which is situated so that after the turret has moved into the position shown in Fig. 5, and during the relative movement of the parts from. stitching position to buttonhole-cutting position the arm 38 will engage the stop member 42.

Hence during the final portion of the rela tive movement between the work-holding means and stitch-forming mechanism from stitchlng to buttonhole-cutting position, the

. arm 38 is in engagement with the stop 'mem ber 42, as shown in dotted dines Fig, 5, and the shaft 36 will thus be turned thereby imoving the pull-ofi arm from the full-line position Fig. 8 to the dotted line position and pulling ofi the desired length of under thread 17. The means for cutting the under thread will be presently described.

It will be remembered that when the stitch-forming mechanism comes to rest at the completion of a buttonhole, the needle 4 is raised and a loop 44 or needle thread is retained by the looper 9, said loop being .held in a spread'o'r open condition by the spreader 11, as seen in Fig. 7.- The construction herein shown is such that the swing.

ing movement of the arm 34 not only draws oi? the under thread, as above described, but also cuts the side 43 of the needle thread loop 44 that leads to the work thereby leaving a cut loop of needle thread on the looper 8. Hence during the movement of the stitchforming mechanism and work-holding means relatively from stitching to buttonhole-cutting position, there will be no added length of needle thread drawn ofi from the source of supply as would be the case if I the loop 44 remained intact. This cutting of the side 43 of the loop 44 of the needle thread is herein accomplished by a cutting edge 45 formed on the arm 34 and situated so that as the arm swings from the full to the dotted line position, Fig. 8, said edge 45 will engage the side 43 of the loop thereby severing it. At this time the loop 44 is spread by the spreader 11 so that the side 46 ofthe loop which leads to the supply is held out of the path of movement of the arm 34 by the spreader. Hence during the relative movement of the stitchforming mechanism and work-holding means from stitching to buttonhole-cutting position, the swinging movement of the arm 34 operates both to draw ofi a length of under thread 17 from the source of supply and also to cut one side of the loop of needle thread.

After the parts have reached buttonholecutting position the work is automatically unclamped by suitable means operating to break the toggle device 28, 29, and immediately. thereafter a thread-cutting device is actuated to cut both the upper and imder threads beneath the work. ln the illustrated embodiment of my invention both the operation of .unclamping the work and of actuating the cutter are accomplished by means of a cam device associated with the main cam 33.

Pivoted at 49 to the housing for thecam 33 is a lever 50, one end 51 of which is I formed on a cam member 53 that is rigid situated to be engaged by a cam face 52 with the main cam 33. The cam face 52 is so situated and shaped that itwill engage the end 51 of the lever just after the parts have completed their movement from stitching to bu'ttonhole-cutting position, the

other end 53 of said lever being situated to engage a toe portion 48 formed on the extension or foot 47 extending from the member 28 of the toggle device. When the toggle device is straightened the toe 48 is in the plane of movement of the end 53 of the lever and when the parts have completed their relative movement into buttonholecutting position the end 53 of the lever is brought into the position relative to the toe indicated in dotted lines Fig. 2. The portion 53 of the lever is cam shaped so that when the lever is actuated by the cam sur face 52 it has a camming action against the under side of the 'toe 48, thus raising the latter sufficiently to break the toggle. The breaking of thetoggle will allow the work clamps 20 to ,be raised by means of the usual sprin As soon as the clamps are raised and t e work unclamped, the threads are cut beneath the work and between the.

latter and the clamp plate. This is accom; plished by a thread-cutting device compris mg the two cutting members 57 and 58 which are pivoted together at 60, and each of which has a cutting edge 59. These cut- I ting members are mounted on the clamp plate 19 so that they can slide back and forth toward and from the throat-plate. 35, such sliding movement being limited by a slot 61 in which the lower-end of the pivotal w pin is received. The rearends of the cutting members 57, '58 are provided with inclined slots 62,63, respectively, in WlllCll is. received a pin 64'carried by an arm 65 fast on a stud 66 that ispivotally mount-- ed in the clamp plate 19. Said stud has rigid therewith another arm 67 which is situated beneath the clamp plate and which is acted upon by a pulling spring 68 that tends to hold it in the position shown in Figs. 2 and 6, in which position the cutting members are retracted and the pin 64 occupies the outer end of the slot 62, 63, while the pin 60 occupies the outer end of the slot 61. When the arm 67 is moved to the left, Fig. 6-, the. resultant swinging moveclined slots 62, 63, thereby closing the cut- I ting edges upon each other and operating to out both upper and under threads. This cutting of the thread is done beneath the work and close to the latter and also between the work and the clamp plate or work-holding means. After the thread has been cut, the parts are allowed to return to the full line position Fig. 6. This movement of the thread trimmer is herein accomplished by means of a roll 69 carried on an arm 70 extending from thecam member 53 and which is adapted to engage-one end 71 of. an arm or'lever 72 that 1s pivot:

ed on a stud 73 carried .by the housing for the main cam 33. Said stud 73 also has rigid therewith another arm 74, the end 75 of which is adapted to engage a pin or extension 76 depending from the arm 67. When the parts are in relative position for stitching, the arm 67 will be separated from the end 75 of the lever, as shown in Fig. 2,

but when the parts are moved relatively to bring them into buttonhole cutting'position, then the pin 76, on the lever 67 is brought into position to be engaged by the end 75of the arm 74 when the latter is actuated by the roll 69. The actionof the roll 69 against the end 71 of the arm 72 is a wiping action, that is, the roll engages the arm, then wipes by the latter. As soon as the roll has passed by the arm, the spring 68 operates automatically to return the cut- I ting members 57,58 to their retracted and '0 en position shown in full lines Fig. 6.

he cutters, therefore, will have a quick forward movement while they are open to bring them into position to engage thd thread andthen a nick closing movement Q to 'cut the'thread, a er which they will be immediately withdrawn to their inoperative position shown in full lines Fig. 6.

The thread-cutting jaws 57, 58 will also operate to sever the stay-cord if one is used. While I have illustrated herein a selected embodiment of my invention, 1 do .not wish to be limited 'to the constructional features shown.

I claim: 7

1. In a sewing machine, the combination with work-holding means and stitch-forming mechanism including upper thread mechanism and under thread mechanism ar- 7 2. Ina sewing machine, the combination with'work-holding means and stitch-forming mechanism mcluding upper thread mechanism and under thread mechanism arranged so that when the machine comes to rest a loop of the upper thread is retained by the under thread mechanism, of means operative after the stitch-forming mechanism comes to rest to cut the side of the loop of upper thread that leads to the work and at the same time to draw out av length of under thread from the supply without cutting said thread and subsequently to cut the under thread.

3. In a sewing machine, the combination with work-holding means and stitch-forming mechanism including upper thread mechanism and under thread mechanism arranged so that when the machine comes. to rest a loop of the upper thread is retained by the under thread mechanism,'of a movable device adapted by its movement to draw out a length of under thread from the supply and to cut the side of the loop of upper thread that leads to the work, another device tocut the under thread and means t actuate said devices. I

4. In a sewing machine, the combination with work-holding means and stitch-form ing mechanism including upper thread mechanism and under thread mechanism arranged so that when the machine comes to rest a loop of the upper thread is retained by the under thread mechanism, of means operative after the stitch-forming mechanism comes to rest to'draw out a length of under thread from the supply and to cut the side of the loop of upper thread that leads to the work and subsequently to cut the under thread between the work and the work-holding means.

5. In a sewing machine, the combination with work-holding means and stitch-forming mechanism including upper thread mechanism and under thread mechanism arranged so that when the machine comes to rest a loop of the upper thread is retained by the under thread mechanism, of a movable device adapted by its movement to draw out a length of under thread from the supply and to cut the side of the loop of upper thread that leads to the work, an-

other device to cut the under thread, and

means to actuate said devices successively.

6. In a sewlng machine, the comblnatlon with work-holding means and stitch-forming mechanism including upper thread mechanism and under thread mechanism arranged so that when the machine comes to rest a loop of upper thread is retained by the under thread mechanism, of a combined pull-ofl' and cutter, and means to actuate the latter after the stitch-forming mechanism comes to rest to cut said loop of upper thread and at the same time to pull ofl a length of under thread without cutting it.

7. In a sewing machine, the combination with work-holding means and stitch-forming mechanism including upper thread mechanism and under thread mechanism arranged so that when the machine comes to rest a loop of upper thread is retained by the under thread mechanism, of a combined pull-off and cutter, means to actuate the latter after the stitch-forming mechanism comes to rest to pull off a length of underv thread without cutting it and cut the side of said loop of upper thread that leads to the work, and other means having an operative movement different from that of the, combined pull-ofi' and cutter to cut the under thread. v

'8. Ina sewing machine, the combination with work-holding means and stitch-forming mechanism including upper thread mechanism and under thread mechanism arranged so that when the machine comesv to rest a loop of upper thread is re-- tained by the under thread mechanism, of a combined pull-off and cutter, means toactuate the latter after the stitch-forming mechanism comes to rest to pull off a length of under thread and cut the side of said loop of upper thread that leads to the work, and means to cut the under thread between the work and the work-holding means. 5 Y

9. In a sewing machine, the combination with work-holding means and stitch-forming mechanism. including upper thread mechanism, under thread mechanism, and a turret on which the under thread mechanism is mounted, of means carried by the turret and operative when the stitch-formnism is mounted, of a combined pull-01f and cutter carried by the turret, and means to actuate the latter after the stitch-forming mechanism comes to rest to pull off a length. of under thread and cut one side of the loop of upper thread.

11. In a sewing machine, the combination with work-holding means and stitch-formthe combination ment at the end of the stitching operation ing mechanism including upper thread -mechanism and under thread mechanism end of the stitching operation to pull off a length of under thread and to cut one side only of the loop of upper thread.

12. In a sewing machine, the combination with work-holdin means and stitch-forming mechanism inclu ing upper thread mechanism and under thread mechanism arranged so that when the machine comes to rest 'a loop of upper thread is retained by the under thread mechanism, said work-holding means and stitch-forming mechanism having a relative movement, of means actuated by said relative movement at the end of the stitching operation to pull off a length of under threadand to cut one side only of the loop of upper thread, and means to cut the under thread beneath the work.

13. In a sewing machine, the combination with work-holding means and stitch-forming mechanism including upper thread mechanism, under thread mechanism and a turret on which the under thread mechanism is mounted, means for giving said workholding means and stitch-forming mechanism a relative movement, and means carried by the turret and rendered operative by such relative movement to pull off a length ofunder thread and cut one side of the loop of upper thread which is retained by the under thread mechanism. 14. In a sewing machine, the combination with stitch-forming mechanisi'n including a turret and under thread mechanism thereon, means for giving the work-holding means and stitching-forming mechanism a relative movement, and means carried by the turret and operated by such relative moveto draw oif a length of under thread.

15. In a sewing machine, the combination with work-holdin means, of stitchforming mechanism inc udin upper thread mechanism and under threa mechanism, a

' turret on which said under thread mecha-- msm is mounted, means carried by the turret and operative when the stitch-forming mechanism comes to rest to draw 01f a length 'of under thread, and means carried by the work-holding means to cut the under thread.

16. Ii a'buttonhole sewing machine, the

combination with work-holding means and stitch-forming mechanism mounted for relative movement from stitching to buttonholecuttingi position, said stitch-forming mechanism including upper thread mechanism and under thread mechanism, a turret on which the under thread mechanism is mounted,

means carried by the turret and rendered operative by such relative movement at the v completion ofa buttonhole to draw oil a length of under thread, and means carried by the work-holding means to cut the under thread.

i 17. In a sewing machine, the combination with work-holding means and stitch-forming mechanism, of a feed cam'for moving said parts relatively, said stitch-forming mechanism including upper thread mechanism and under thread mechanism, a turret on which the under thread mechanism is mounted, means carried by said turret and operated by such relative movement to draw off a length of under'thread at the completion of the stitching operation, and means actuated by said cam to cut the under thread after the latter has been drawn ofl.

18. In a buttonhole sewing machine, the

combination with work-holding means, of

stitch-forming mechanism, the latter including upper thread mechanism and under thread mechanism, a turret on which the under thread mechanism is mounted, means carried by the turret to draw ofl a length of under thread at the completion of the stitching operation and to cut the upper thread, and means carried by the work-holding means to cut the under thread.

19. In a sewing machine, the combination with work-holding means, of stitch-forming mechanism including upper thread mechanism and under thread mechanism, a turret on ,which the under thread-mechanism is mounted, means carried by the turret for cutting the upper thread, and means carried bythe work-holding meansfor cutting the under thread.

. 20. In a sewing-machine, the combination with work-holding means including 'a clamp plate a st which the work is clamped, of under t read mechanism beneath the clamp plate, upper thread mechanism above the clamp plate, means beneath the clamp plate to pull ofi a length of under thread andto cut the upper thread, and means above the clamp plate to cut the under. thread.

- In te'stimonywhereof, I have signed my name to this specification.

JOHN 'KIEWICZ. 

